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When to Plant Chayote in Whatcom County, WA

Chayote is a tropical vine producing pear-shaped, mild-flavored squash. The entire plant is edible including the fruit, shoots, leaves, and tuberous root.

Whatcom County, Washington is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 29, giving you a growing season of approximately 206 days.

At an elevation of 386 feet, Whatcom County receives approximately 49 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Chayote during the growing season.

Whatcom County, WA (Zone 7b) Long season
206 days
Last Spring Frost April 6
206 growing days
First Fall Frost October 29

Whatcom County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 4 Transplant: Apr 8 🍅 Harvest: Aug 12 – Oct 21
Recommended (50%) ✗ May not fit
Start indoors: Feb 16 Transplant: Apr 20 🍅 Harvest: Aug 24 – Nov 2
Safe Start (90%) ✗ May not fit
Start indoors: Mar 18 Transplant: May 20 🍅 Harvest: Sep 23 – Dec 2

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Whatcom County

How your county's soil matches Chayote's growing requirements.

Soil pH

Your soil pH (5.2โ€“6.4) is more acidic than Chayote prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Whatcom County is excellent for Chayote โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.7%) โ€” Chayote will thrive.

How to Plant Chayote

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Only during dry spells
Season total 2 gal / 100 sq ft
Chayote needs ~2,062 GDD — county provides 2,832 GDD Excellent fit

Chayote Planting Timeline โ€” Whatcom County, WA

Chayote Planting Calendar

Activity When Date Range
Start Indoors February 16 Feb 16 โ€“ Mar 2
Transplant Outdoors April 20 Apr 20 โ€“ May 4
Direct Sow April 13 Apr 13 โ€“ May 4
Harvest August 24 Aug 24 โ€“ Nov 2

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July โ€”
August Harvest
September Harvest
October Harvest
November Harvest
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

120โ€“180 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

206 days in Whatcom County

Growing Tips for Chayote in Whatcom County

Direct sow Chayote outdoors after April 06 in Whatcom County when soil has warmed and frost danger has passed.

Common pests for Chayote in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant the whole fruit at a 45-degree angle with the stem end exposed. Provide a very sturdy trellis. One vine can produce 60-80 fruits. Harvest when fruits are young and tender.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Chayote in Whatcom County, WA?

Whatcom County is in Zone 7b with an average last frost of April 6. Plan your Chayote planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Whatcom County, WA?

Whatcom County, Washington is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Whatcom County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Whatcom County, WA. Local conditions may vary. Last updated: April 2026.